Gear wheel



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W. E. MOORE GEAR WHEEL Filed Oct. 27 1920 2 Sheets-Sheet vvuam/to'c miliammjwbawe,

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v N T STATESIPATENT omE MOORE, OF-IBEA'V'EE FALLS, PENNSYLVANIA, ASSIGNOR TO EITTSBUBfl-H RESEARCH CORPOBATIDN, A CORPORATION OF DELAWARE.

em WHEEL.

, Application filed October-27, ma Serial no. 419,520.

To all whom it may concern:

Be it known that I, WILLIAM E. Moore, a citizen of the United States of America, residin at Beaver Falls, in the county of Beaver and seas of Pennsylvania, have inspecification.

This invention relatesto' gear wheels and to the process of making such wheels. My invention is also applicable to the manufacture of friction wheels and rollers, pulleys,

and similar elements.

An object of my invention is the production of a Wheel from a. wooden blank made up of thin layers of wood cemented .together, prefera 1y with waterproof elastic cement pressure bein applie during the cementing process, an while the cement isfluid, to force the cement into the pores of the wood, thoroughly permeating it, and to compress the wood to twenty fiveto seventyfive per cent or less-of its original thickness.

Instead of waterproof cement I may use such materials ascelluloid, bakelite, hard rubber or other cement whichmay be vulcanized into the wood.

Another object of my invention is the production of a wheel which .is water and oil proot and also noiseless. I A still further object of my invention is the saturation of the wood layers with waterproof elastic cement, and then the setting of the cement while the layers are under high pressure. The layers are preferably placed with the grain of each layer crossing at an iangle of 90 or less to the grain of the next a er.

. It has been found that the thickness of the layers should be less than the thickness of the tooth which is formed on the periphery of the blank; otherwise I have found that the wear is increased, the strength is re- A duced, and there is a tendency of thew'ood ted to the armature or other wire; of themotor, quickly Wearing out the insulation and causing short circuits,

-spinnable fibre placed between metal end vented certain new and useful Improvements in Gear Wheels, of which the following is'a' built up of thick wooden non-compress d usually been costly or weak andnon-durable and suitable only for very light service.

In wheels made of comparatively thick wood flanges. Such structures, however, have I held with glue, the wood is-subject to expansion due to atmospheric. changes and is readily damaged by absorption of oil or water. M invention doesaway withthese object ons y permeating all the pores with a waterproof elastic cement and by making the layers of very thin material, readily.

permeable by the cement and non spawling. In some cases I prefer to make -up the wood disc of sector shaped pieces in layers.

These sectors or pie sections usually have the grain running in a radial direction. The

radial edges of such sections may be beveled to make them stronger than butt joints wherever suc-h joints may appear in the gear tooth after'cutting.

My invention is also applicable to crown gears and other forms of wheels. In making crown gears thin cement permeable layers are wound around the metal or other spider and thelayers are compressed with a waterproof adhesive between them in the same way that spur gear wheels and other simi-' lar elements are constructed. The grain of one layer in the .crown gear construction is laced radially with the grain of alternate I ayers placed at an angle thereto.

I have also found that material constructed inaccordance with my process is a good insulator and may be used for filling discs between insulating couplings, or for insulat ing parts of electrical apparatus and machinery,' such as terminal boards and similar devices, in which case it is sometimes desirable further to treat the block, after it has been properly formed and fitted, with a suitable varnish. 'After this coating has been applied, the block may be baked.

In. some cases I find it is desirable to put intermediate layers between the wood layers, such layers consisting of high-strength paper, fibre, cloth, or very thin metal.

Figure 2" is a section on the line 22 of F igure'l;

Figure 3 is a plan View of a modified form of construct on of spur gear;

ment hardens. I do not, however, limit In Figure 4 is an enlarged section on the line 4-4 of Figure 3;

Figure 5 is a section of a modified form of gear showing thin layers of material between the wood layers;

Figure 6 's a plan view of a bevel gear with a metal spider;

' Figure 7 is a section on the line 7-7 of Figure 6; and i Fi re 8 is a fragment of a section of a whee showing the construction of a crown gear, the general construction of the wheel being the same as shown in Figure 6.

The gear illustrated in Figures 1 and 2, which is designated as a whole by the numeral 1, is made up. of discs of thin layers of wood or veneer 2 consisting of any suitable number, ten being shown. These thin layers may be of wood of a character having pores which may be filled by a waterproof elastic cement placed between the layers and forced into the pores of the thin layers by pressure. The layers are placed so that the grain of each layer will be at an angle of 90 or less to the rain ofthe next layers. In forming the bIanks to construct a wheel, I prefer to use hydraulic pressure and to subject the Wood to a degree of compression sufficient to cause the cement to permeate the fibres and at the same time to'densify by compression the'fibres to a maximum degree without crushing or weakening the fibres. That 'is to say, the pressure applied is suflicient to compress the fibres beyond their elastic compressive strength and to increase the number of fibres per unit thickness but not great enough to compress the fibres until they become a pulp and also not great enough to'reduce materially the strength of the fibres. The layers are then held under pressure while the ceinvention to a highlycompressed blank, but may use any degree of compression that seems desirable .under the circumstances, and may use a vacuumpress or air or fluid pressure to cause the compression and to fill the pores of the wood with the cement.

After the adhesive has vulcanized or set and the blank has hardened, the necessary opening 3 for a shaft may be made, a metal hub 4 may be attached as shown, in an metal flanges 6 may be attached by rivets or bolts"7.' These flanges may be attached before the teeth 8 are cut. The teeth are cut by any of the Well known means of cuty of wood, said layers being held suitable manner, as by rivets or bolts 5, and

ting gear teeth through the metal and the layers of wood.

In Figure 5 is illustrated the use of material between the layers of wood. lfiach layer is shown as having between it and the adjacent layer a thin layer 9 of highstrength paper, fibre, cloth, .or very thin metal.

In Figures 3 and 1 a gear wheel of a slightly modified construction is shown. This wheel is made up of six pie-shaped sectors 10 having the grain generally radial, but the sectors are so arranged that the grain of each layer is at an angle to the :ut jacent layer. These sectors are beveled as shown at 11 in Figure 4, and the joints are staggered in order to strengthen the struc- In Figures 6 and 7 the construction of a bevel gear in accordance with my invention is illustrated. In this form of wheel a metal spider 12 of the ordinary construction is used. Around the periphery 13 of this spider are placed a suitable number of thin layers of wood 14, seven being shown. The grain of the wood in each layer is placed at an angle to the grain of the wood in an adjoining layer. It is found preferable to have the grain of the wood generally vertical. Around the outer layer is placed a metal band 15. The layers and outer metal bandare attached to the wheel by any suitable means, such as bolts or rivets 16.

In Figure 8 the construction of a crown gear is shown. This structure is identical. with the construction of a bevel gear, except in the shape of the tooth portion 17, which is similar to the tooth of the spur gear.

I claim:

1. The process of producing a gear blank comprising superimposing thin layers of wood, placing a cement between said layers, applying sufficient pressure to change the thickness of said layers to approximately twenty-five per cent of the original thickness of the layers and to force said cement into the pores of the wood of said layers and y continuing said pressure until the cement 2. A gear wheel comprising thin layers of wood, said layers being held together by waterproof elastic cement, said layers having the pores thereof saturated with said cement and said layers being reduced by compression to approximately twenty-five per cent of their original thickness.

3. A gear wheel comprising thin layers together by waterproof elastic cement, said layers having the pores thereof saturated with said cement and said layers being reduced by compresslon to approximately twenty-five per cent of their original thickness and said gear wheel haying teeth thereon greater in t ickness than the thickness of the layers of wood from which said gear wheel is made.

4. The process of producing a gear blank comprising superimposing thin la ers of wood, placing a cement between sai layers, applying suflicient pressure to compress the fibres of the layers beyond their elastic compressive strength and to increase the number of fibres per unit thickness without compressing the fibres sufliciently to reduce their strength materially and to reduce them to a pulp and to force said cement into the pores of said layers of wood and continuing sald pressure until the cement sets.

5. A gear wheel comprising thin layers of wood, said layers being held together by waterproof elastic cement, said layers having the pores thereof saturated with said cement, and said layers being reduced by compression until the fibres thereof have been compressed beyond their elastic comfplressive strength and until the number of bres per unit thickness has increased and without compressing the fibres to a pulp and without reducing the strength of the fibres materially.

In testimony whereof I afiix my signature.

WILLIAM E. MOORE. I 

